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Publication costs assisted by Fonds der Chemie, Frankfurt these bonds as the bonds of cyclic dimers and linear higher polymers, as suggested by previous authors. However, due to the complications of the alcohol association as well as to the inherent simplifications of the model the calculated energies may not be related to the bonds in a simple manner. From K2 and K3 the activity coefficients and the excess free energy can be recalculated. The comparison of the obtained values with the conventionally calculated values proves that the amines and the short chain alcohols fit the two-constant model within a wide range of concentrations, while this is not the case with long chain alcohols.

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limit; while the other phase (ß) is present alone wherever this limit is exceeded. They also make plain the migration of the phase boundary with continued diffusion. Finally they show that the higher order diffraction lines from the ß phase are much less intense than those of the a phase, a fact probably due to the severe cold working which occurs as ß is formed from a by a sudden expansion of over 3% (linear) at the advancing phase boundary.

This paper is dedicated to Professor Camille Sandorb on the occasion of his 65th birthdayHANS WOLFF and JERZY SZYDLOWSKI. Can. J. Chem. 63, 1708Chem. 63, (1985.The infrared spectra of gaseous, liquid, and solid CZHsSD, and the Raman spectrum of the liquid compound are analyzed and the corresponding spectra of C2H5SH were reinvestigated under improved conditions. In the deuterated compound the CH2 rocking vibration does not interact with the SD bending vibration and therefore does not split into vibrations of the conformers. The measurements suggest for gaseous and liquid CzHSSH and CZHsSD the simultaneous presence of the trarzs and gauche conformers, appearing at room temperature in the ratio of the order of 1 : 3. In analogy to solid CzHsSH, the exclusive presence of the gauche conformers can be inferred for solid C2HsSD. The spectra reported in the literature for the C2HsSH molecules embedded in matrices at low temperatures permit a similar interpretation. The doublet structure observed for the vibrational bands, not only of pure solid C,H5SH and CZHsSD but also of their solid mixtures, may be due to non-equivalent sites of the unit cell.HANS WOLFF et JERZY SZYDLOWSKI. Can. J. Chem. 63, 1708Chem. 63, (1985.On a analysC les spectres infrarouges du C2H5SD dans les Ctats gazeux, liquide et solide, le spectre Raman du composC liquide ainsi que les spectres correspondants du C,H5SH qui ont Ct C rCexaminCs dans des conditions amCliorCes. Dans le composC deutCrC, la vibration de rocking du CH2 n'interfkre pas avec la vibration de dCformation du SD; elle ne se sCpare donc pas en vibrations des conformkres. Dans les composCs C2H5SH et C2HsSD gazeux ou liquides, les mesures a la tempirature ambiante suggerent que les conformkres gauche et trans existent simultanCment dans des rapports de 1 : 3. Par analogie avec les rCsultats obtenus avec la C,HsSH, on peut suggCrer que le C2H5SD a I'Ctat solide existe exclusivement sous la conformation gauche. Sur la base des spectres rapportCs dans la IittCrature pour des molCcules de C2H5SH imbriqukes dans des matrices a basses temptratures, on peut proposer une interprktation semblable. La presence de doublets qui ont Ct C observCs dans les bandes vibrationnelles, non seulement du C2HsSH et du C2H5SD purs a 1'Ctat solide mais aussi dans leurs mClanges solides, pourrait &tre due a des sites qui ne sont pas Cquivalents dans la maille unitaire.[ Traduit par le journal]A. Introduction and measurements For ethanethiol one trarzs form and two equivalent gauche forms are to be considered. The manifestation of these forms in the vibrational spectra has been studied in low temperature infrared spectra including those of matrices and especially in infrared and Raman spectra in the range of torsional transitions (1 -7). Some of these investigations have also been performed for C,H5SD. However, there has been no systematic infrared study of the deuterated compound. To fill in the blanks and to expand the investigations on rotational isomerism of ethanethiol, the infrared spectra of gaseous,...